JP2007002187A - Thermosetting resin composition, and prepreg, substrate and conductive foil-clad substrate, using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin composition having excellent dielectric characteristics in a high frequency region, heat resistance and mechanical strength, and usable for forming a substrate having sufficient flame retardancy. <P>SOLUTION: The thermosetting resin composition comprises a vinyl benzyl ether compound represented by general formula (1) [wherein, R<SP>1</SP>is a methyl group or an ethyl group; R<SP>2</SP>is a hydrogen atom or a 1-10C hydrocarbon group; and n is an integer of 2-6], an aromatic phosphoric acid ester, a benzoxazine compound regulated so that the content of the aromatic phosphoric acid ester is 50-80 pts.mass, and the content of the benzoxazine compound is 5-40 pts.mass based on 100 pts.mass of the vinyl benzyl ether. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermosetting resin composition, a prepreg using the same, a substrate and a substrate with a conductive foil, and more specifically, a thermosetting resin composition used for a flame-retardant substrate suitable for use in a high-frequency region. The present invention relates to an object, a prepreg using the same, a substrate, and a substrate with a conductive foil.

  In recent years, there has been a marked trend toward smaller and higher-density mounting methods in the field of electronic equipment for communications, consumer use, industrial use, etc. , Dimensional stability and electrical characteristics are being demanded.

  For example, as a printed wiring board, a copper-clad laminate based on a thermosetting resin such as a phenol resin or an epoxy resin has been conventionally used. However, these have various performances in a well-balanced manner, but have the problem of poor electrical characteristics, particularly dielectric characteristics in a high frequency region.

As a material for improving this problem, for example, a polyvinyl benzyl ether compound described in Patent Document 1 below has been proposed. This polyvinyl benzyl ether compound has excellent electrical properties, heat resistance, reliability, and excellent adhesion to various materials, and is characterized by its thermosetting resin composition, prepreg, copper-clad Attempts have been made to apply it to laminates and the like.
JP-A-9-31006

  However, polyvinyl benzyl ether compounds are flammable materials, and safety problems have been pointed out when applied to multilayer substrates and electronic components. For this reason, in order to impart flame retardancy to a substrate using a polyvinyl benzyl ether compound, it is necessary to add a large amount of a flame retardant. However, when a large amount of flame retardant is added, there arises a problem that physical properties such as dielectric properties, heat resistance and mechanical strength are remarkably lowered.

  The present invention has been made in view of the above-described problems of the prior art, and is for forming a substrate having excellent dielectric properties, heat resistance, and mechanical strength in a high-frequency region and having sufficient flame retardancy. It aims at providing a thermosetting resin composition, a prepreg using the same, a board | substrate, and a board | substrate with conductor foil.

［式中、Ｒ^１はメチル基又はエチル基を示し、Ｒ^２は水素原子又は炭素数１〜１０の炭化水素基を示し、ｎは２〜６の整数を示す。］ In order to achieve the above object, the present invention includes a vinyl benzyl ether compound represented by the following general formula (1), an aromatic phosphate ester, and a benzoxazine compound, and 100 parts by mass of the vinyl benzyl ether compound. The thermosetting resin composition is characterized in that the content of the aromatic phosphate is 50 to 80 parts by mass and the content of the benzoxazine compound is 5 to 40 parts by mass. To do.

[Wherein, R ¹ represents a methyl group or an ethyl group, R ² represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 2 to 6. ]

  In such a thermosetting resin composition, when a substrate is formed by using a vinyl benzyl ether compound as a thermosetting resin, excellent dielectric properties in a high frequency region (for example, 1 GHz or more), high heat resistance, and High mechanical strength can be obtained. Further, in the thermosetting resin composition using the vinyl benzyl ether compound, the aromatic phosphate ester has excellent hydrolysis resistance by using the aromatic phosphate ester in the above range as a flame retardant. Therefore, when the substrate is formed, excellent flame retardancy can be obtained without impairing the excellent dielectric properties of the vinyl benzyl ether compound. Furthermore, by using the benzoxazine compound in an amount within the above range together with the aromatic phosphate ester, the deterioration of physical properties such as heat resistance, mechanical strength and copper foil adhesion due to the addition of the aromatic phosphate ester is suppressed. It is possible to achieve both of these physical properties and flame retardancy. As a result, according to the thermosetting resin composition of the present invention, when the substrate is formed, all of flame retardancy, dielectric properties in the high frequency region, heat resistance and mechanical strength can be achieved at a high level. it can.

  Furthermore, according to the said thermosetting resin composition, while being able to form the board | substrate which has the outstanding solvent resistance and copper foil adhesiveness, by using the flame retardant which does not contain a halogen, it is environmental. The load can be reduced.

［式中、Ｑは芳香環を有する２価の有機基又は炭素数２〜１４の２価の脂肪族炭化水素基を示し、Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は各々独立に水素原子又は炭素数１〜６のアルキル基を示し、ｋは１以上の整数を示し、ｍ^１、ｍ^２、ｍ^３及びｍ^４は各々独立に１〜３の整数を示す。］ Moreover, in the thermosetting resin composition of this invention, it is preferable that the said aromatic phosphate ester is what is represented by following General formula (2).

[Wherein Q represents a divalent organic group having an aromatic ring or a divalent aliphatic hydrocarbon group having 2 to 14 carbon atoms, and R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom. Alternatively, it represents an alkyl group having 1 to 6 carbon atoms, k represents an integer of 1 or more, and m ¹ , m ² , m ³ and m ⁴ each independently represents an integer of 1 to 3. ]

  By using such an aromatic phosphate ester, the thermosetting resin composition can form a substrate that achieves a higher level of dielectric properties and flame retardancy in the high frequency region.

  Moreover, it is preferable that the thermosetting resin composition of this invention further contains the inorganic filler whose dielectric loss tangent in the high frequency band of 2 GHz or more is 0.003 or less.

  By adding the inorganic filler to the thermosetting resin composition, the dielectric properties of the substrate to be formed can be improved, and in particular, the dielectric loss tangent can be reduced. Moreover, while being able to control the fluidity | liquidity of a thermosetting resin composition, the thermal expansion coefficient of the board | substrate formed can be reduced.

  In addition, it is preferable that content of the said inorganic filler is 10-50 volume% on the basis of the solid content whole volume in a thermosetting resin composition from a viewpoint of acquiring the said effect more fully.

  Moreover, it is preferable that the thermosetting resin composition of this invention further contains a radical polymerization initiator.

  By adding a radical polymerization initiator to the thermosetting resin composition, it accelerates the curing (crosslinking reaction) of the vinyl benzyl ether compound and improves the solvent resistance, heat resistance and mechanical strength of the substrate to be formed. Can do.

  In addition, it is preferable that content of the said radical polymerization initiator is 0.1-3.0 mass parts with respect to 100 mass parts of said vinyl benzyl ether compounds from a viewpoint of acquiring the said effect more fully.

  The present invention also provides a prepreg comprising a substrate impregnated with the thermosetting resin composition of the present invention.

  Since such a prepreg is formed using the thermosetting resin composition of the present invention, when it is cured to form a substrate, all of flame retardancy, dielectric properties, heat resistance, and mechanical strength are exhibited. It can be achieved at a high level, and excellent solvent resistance and copper foil adhesion can be obtained. Moreover, the use of a flame retardant that does not contain halogen can reduce the environmental load.

  Here, the substrate is preferably at least one selected from the group consisting of a glass nonwoven fabric, a glass cloth, and an aramid nonwoven fabric.

  The present invention also provides a substrate comprising a resin layer obtained by curing the thermosetting resin composition of the present invention.

  The present invention also provides a substrate comprising a resin layer formed by curing the thermosetting resin composition in the prepreg of the present invention.

  The present invention also includes a substrate with a conductive foil, comprising: a resin layer obtained by curing the thermosetting resin composition of the present invention; and a conductive foil disposed on the surface of the resin layer. provide.

  The present invention further comprises a resin layer obtained by curing the thermosetting resin composition in the prepreg of the present invention, and a conductor foil disposed on the surface of the resin layer. Provided with a substrate.

  Since these substrates and substrates with conductive foil are both formed using the thermosetting resin composition of the present invention, all of flame retardancy, dielectric properties, heat resistance, and mechanical strength are at a high level. Furthermore, excellent solvent resistance and copper foil adhesion can be obtained. Moreover, the use of a flame retardant that does not contain halogen can reduce the environmental load.

  According to the present invention, a thermosetting resin composition for forming a substrate having excellent dielectric properties, heat resistance, and mechanical strength in a high frequency region and having sufficient flame retardancy, and the same are used. A prepreg, a substrate, and a substrate with a conductive foil can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as the case may be. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

  First, the thermosetting resin composition of the present invention will be described.

［式中、Ｒ^１はメチル基又はエチル基を示し、Ｒ^２は水素原子又は炭素数１〜１０の炭化水素基を示し、ｎは２〜６の整数を示す。］ The thermosetting resin composition of the present invention includes a vinyl benzyl ether compound represented by the following general formula (1), an aromatic phosphate ester, and a benzoxazine compound, and 100 parts by mass of the vinyl benzyl ether compound. On the other hand, the content of the aromatic phosphate is 50 to 80 parts by mass, and the content of the benzoxazine compound is 5 to 40 parts by mass.

[Wherein, R ¹ represents a methyl group or an ethyl group, R ² represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 2 to 6. ]

［式中、Ｒ^１、Ｒ^２及びｎは、上記一般式（１）におけるＲ^１、Ｒ^２及びｎと同義である。］ Here, the vinyl benzyl ether compound represented by the general formula (1) is, for example, a reaction between polyphenol represented by the following general formula (3) and vinyl benzyl halide in the presence of an alkali metal hydroxide. Can be obtained.

^[Wherein, R 1, ^{R 2} and n have the same meanings as ^R 1, ^{R 2} and n in the general formula (1). ]

  As the polyphenol represented by the general formula (3), commercially available products can be used as appropriate, for example, PP-700-300 and PP-1000-180 manufactured by Shin Nippon Petrochemical Co., Ltd. are used. be able to.

  Examples of the vinyl benzyl halide include p-vinyl benzyl chloride, m-vinyl benzyl chloride, a mixture of p-vinyl benzyl chloride and m-vinyl benzyl chloride, p-vinyl benzyl bromide, m-vinyl benzyl bromide and p- Examples thereof include a mixture of vinyl benzyl bromide and m-vinyl benzyl bromide. Of these, p-vinylbenzyl chloride and a mixture of p-vinylbenzyl chloride and m-vinylbenzyl chloride are preferably used. When p-vinylbenzyl chloride is used, a vinylbenzyl ether compound having a high melting point and a high softening point can be obtained. Further, when a mixture of p-vinylbenzyl chloride and m-vinylbenzyl chloride is used, a vinylbenzyl ether compound having a low melting point and a low softening point is obtained, and the workability is improved.

  The reaction between polyphenol and vinylbenzyl halide is not particularly limited. For example, polyphenol and vinylbenzyl halide are reacted in a polar neutral solvent using an alkali metal hydroxide as a dehydrohalogenating agent. It can be performed by the method of making it. The blending ratio of polyphenol and vinylbenzyl halide can be adjusted as appropriate. For example, the molar ratio of polyphenol: hydroxyl group of vinylphenol: vinylbenzyl halide = 100: 40 to 100: 120.

  Examples of polar neutral solvents include dimethylformamide, dimethyl sulfoxide, dimethylacetamide, N-methylpyrrolidone, dioxane, acetonitrile, tetrahydrofuran, ethylene glycol dimethyl ether, 1,3-dimethoxypropane, 1,2-dimethoxypropane, tetramethylenesulfone, hexa Examples thereof include methyl phosphoamide, methyl ethyl ketone, methyl isobutyl ketone, acetone and a mixture thereof.

  Examples of the alkali metal hydroxide include potassium hydroxide, sodium hydroxide and a mixture thereof. The blending ratio of the alkali metal hydroxide is preferably about 1.1 to 2.0 times mol for 1 mol of phenolic hydroxyl group, for example. In this case, the reaction temperature and the reaction time may be 30 to 100 ° C. and about 0.5 to 20 hours, respectively.

  As another method, the polyphenol and vinylbenzyl halide are removed from the alkali metal hydroxide in a water / organic solvent mixture in the presence of a phase transfer catalyst such as a quaternary ammonium salt. The vinylbenzyl ether compound according to the present invention can be obtained by reacting at a temperature up to 100 ° C. as a hydrogen halide agent. In this case, unreacted raw materials and the like can be removed by using a blending design of polyphenol and vinylbenzyl halide and an appropriate means, for example, a reprecipitation purification method using a solvent / non-solvent system combination. Is possible.

  Specific examples of the vinyl benzyl ether compound represented by the general formula (1) include ARS068 (trade name, manufactured by Showa Polymer Co., Ltd.). These vinyl benzyl ether compounds can be used individually by 1 type or in combination of 2 or more types.

  Moreover, although it does not restrict | limit especially as an aromatic phosphate ester, The aromatic phosphate ester represented by following General formula (2) is mentioned as a preferable thing.

［式中、Ｑは芳香環を有する２価の有機基又は炭素数２〜１４の２価の脂肪族炭化水素基を示し、Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は各々独立に水素原子又は炭素数１〜６のアルキル基を示し、ｋは１以上の整数を示し、ｍ^１、ｍ^２、ｍ^３及びｍ^４は各々独立に１〜３の整数を示す。］

[Wherein Q represents a divalent organic group having an aromatic ring or a divalent aliphatic hydrocarbon group having 2 to 14 carbon atoms, and R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom. Alternatively, it represents an alkyl group having 1 to 6 carbon atoms, k represents an integer of 1 or more, and m ¹ , m ² , m ³ and m ⁴ each independently represents an integer of 1 to 3. ]

  Examples of such phosphate esters include resorcinol bis (2,6-xylenyl phosphate), resorcinol bis (2,6-phenyl phosphate), hydroquinone tetra (2,6-xylenyl phosphate), hydroquinone tetra (2,6-phenyl phosphate), bisphenol A-bis (2,6-xylenyl phosphate), bisphenol A-bis (2,6-phenyl phosphate) and the like. These aromatic phosphate esters can be used singly or in combination of two or more.

  Further, the content of the aromatic phosphate ester in the curable resin composition needs to be 50 to 80 parts by mass with respect to 100 parts by mass of the above-mentioned vinyl benzyl ether compound, and is 60 to 80. preferable. When this content is less than 50 parts by mass, the flame retardance of the substrate to be formed becomes insufficient, and when it exceeds 80 parts by mass, the physical properties such as heat resistance and mechanical strength of the substrate to be formed are insufficient. Become.

  Moreover, as a benzoxazine compound, the compound represented by following General formula (4) can be mentioned as a preferable thing.

［式中、Ｒ^７はアルキル基又はアリール基を示し、Ｒ^８は下記式（Ｉ）〜（ＸＶＩＩＩ）で表わされる有機基を示し、ｐは１〜４の整数を示す。］

[Wherein, R ⁷ represents an alkyl group or an aryl group, R ⁸ represents an organic group represented by the following formulas (I) to (XVIII), and p represents an integer of 1 to 4. ]

［上記式（ＸＶＩＩＩ）中、Ｒ^７は上記一般式（４）におけるＲ^７と同義である。］

[In the formula (XVIII), ^{R 7} has the same meaning as ^{R 7} in the general formula (4). ]

  Further, the content of the benzoxazine compound in the curable resin composition is required to be 5 to 40 parts by mass with respect to 100 parts by mass of the above-mentioned vinyl benzyl ether compound, and preferably 10 to 20. If this content is less than 5 parts by mass, the heat resistance, mechanical strength and copper foil adhesion of the substrate to be formed will be insufficient, and if it exceeds 40 parts by mass, the dielectric properties of the substrate to be formed (particularly dielectric) Tangent) is insufficient.

  The thermosetting resin composition of the present invention only needs to contain the vinyl benzyl ether compound, the aromatic phosphate ester, and the benzoxazine compound, and other additives are particularly limited. Although not intended, it is preferable that the additive further includes an inorganic filler having a dielectric loss tangent of 0.003 or less in a high frequency band of 2 GHz or more.

  The inorganic filler is not particularly limited as long as the dielectric loss tangent tan δ in a high frequency band of 2 GHz or more is 0.003 or less, and examples thereof include inorganic fillers such as barium titanate compounds, silica, alumina, zirconia, and the like. It is done.

  By adding these inorganic fillers, the dielectric properties of the substrate to be formed can be adjusted, and in particular, the dielectric loss tangent can be lowered. Moreover, while being able to control the fluidity | liquidity of a thermosetting resin composition, the thermal expansion coefficient of the board | substrate formed can be reduced.

  The content of the inorganic filler in the curable resin composition is preferably 50% by volume or less, more preferably 10 to 50% by volume, based on the total volume of the solid content in the thermosetting resin composition. It is preferably 10 to 45% by volume, more preferably 20 to 40% by volume. In particular, when adjusting the relative permittivity ε ′ by adding an inorganic filler, if the content is less than 10% by volume, the change in the relative permittivity ε ′ tends to be insufficient, and exceeds 50% by volume. Then, the resin composition is difficult to mold, and the production of the substrate tends to be difficult.

  Moreover, in order to accelerate | stimulate hardening (crosslinking reaction) of a vinyl benzyl ether compound, it is preferable to further add a radical polymerization initiator to the thermosetting resin composition of this invention.

  The radical polymerization initiator is not particularly limited, and examples thereof include dicumyl peroxide, t-butylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and the like. Examples thereof include nitrogen-based polymerization initiators such as organic peroxides, azobisibutyronitrile, and azobis (methylbutyronitrile).

  By adding these radical polymerization initiators, the solvent resistance, heat resistance and mechanical strength of the substrate to be formed can be further improved.

  The content of the radical polymerization initiator in the curable resin composition is preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the above-mentioned vinyl benzyl ether compound, and 0.3 to 2 parts by mass. More preferably, it is more preferably 0.5 to 1.0 part by mass. When this content is less than 0.1 part by mass, curing of the vinyl benzyl ether compound is not sufficiently promoted, and the solvent resistance, heat resistance and mechanical strength of the substrate to be formed tend to be insufficient. When the amount exceeds 3.0 parts by mass, the substrate tends to become brittle, the additive is decomposed, and deformed.

  In addition, a polymerization inhibitor such as phenothiazine and tetramethylhydroquinone can be added to the thermosetting resin composition of the present invention as long as it does not impair the object of the present invention.

  Furthermore, a plasticizer, a deterioration preventing agent, and the like can be added to the thermosetting resin composition of the present invention as long as the purpose of the present invention is not impaired.

  Moreover, the thermosetting resin composition of this invention can mix each material mentioned above with a solvent, and can be used as a thermosetting resin composition solution. Although it does not restrict | limit especially as said solvent, It is preferable that it is what can melt | dissolve the above-mentioned vinyl benzyl ether compound and a benzoxazine compound, For example, toluene, xylene, benzene etc. are mentioned.

  Next, the prepreg of the present invention will be described.

  The prepreg of the present invention is obtained by impregnating a substrate with the above-described thermosetting resin composition of the present invention.

  Here, as the substrate, fibers made of glass, aramid, quartz, liquid crystal polymer, or the like, or woven fabrics and nonwoven fabrics made of these fibers are used. Among these, glass nonwoven fabrics, glass cloths, and aramid nonwoven fabrics are used. Preferably, a glass cloth is more preferable in terms of price and performance (strength etc.) as a fiber base material.

  When impregnating a substrate such as glass cloth with a thermosetting resin composition, a monomer or prepolymer of a vinyl benzyl ether compound, an aromatic phosphate ester, a benzoxazine compound, an inorganic filler, a radical polymerization initiator, etc. Are preferably impregnated as a solution dissolved and / or dispersed in the above-described solvent. In this case, the proportion of solids (vinyl benzyl ether compound, aromatic phosphate ester, benzoxazine compound and additive) other than the above solvent in the solution is 40 to 70% by mass based on the total amount of the solution. It is preferable to do so. This thermosetting resin composition solution is generally impregnated into a glass cloth or the like to form a prepreg, and then laminated with a metal foil or the like to form a substrate, but the solid content concentration in the solution is less than 40% by mass. In comparison with the case where the solid content concentration is in the above range, the resin component contained in the prepreg tends to decrease the dielectric properties, whereas when the solid content concentration exceeds 70% by mass, Compared with the case where the solid content concentration is within the above range, the solubility of the solid content in the solvent is deteriorated, and the thickness of the prepreg and the pressed product tends to vary greatly.

  In addition, when glass cloth is used as the prepreg substrate, the material of the glass cloth is not particularly limited, and those commonly used in printed circuit boards can be used. For example, warp yarns and weft yarns constituting the glass cloth can be used. The number per unit length, the thickness, and the weight per unit area correspond to Japanese Industrial Standard R-3414 or American Military Standard (MIL Standard). Moreover, the glass cloth of the range which does not correspond to these specifications may be used, and the mixed textiles of glass fibers and fibers other than glass fibers, such as a carbon fiber or a ceramic fiber, may be sufficient. As this glass fiber, E glass (relative dielectric constant ε ′ = 7, dielectric loss tangent tan δ = 0.003, 1 GHz), D glass (ε = 4, tan δ = 0.0013, 1 GHz), H glass (ε = 11) Tan δ = 0.003, 1 GHz), C glass, S glass, NE glass, and other glass component compositions. From the viewpoint of balance between cost and dielectric properties, E glass is preferred.

  The thickness of the substrate such as glass cloth is not particularly limited, and those having a thickness of 10 to 300 μm, particularly about 50 to 200 μm, and further 50, 100, 150, and 180 μm can be used as necessary. .

  Further, it is preferable that a substrate such as a glass cloth is subjected to a surface treatment in advance in order to improve the adhesion between the resin impregnated inside the yarn bundle and the glass fiber. Examples of the surface treatment agent used for the surface treatment include silane coupling agents such as aminosilane compounds, vinylsilane compounds, styrene silane compounds, and methacrylsilane compounds. Among these, a methacryl silane type and a vinyl silane type are suitable in combination with a vinyl benzyl ether compound. Preferred examples of the methacrylic silane compound include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, and the like.

  As the surface treatment method of the substrate such as glass cloth with the coupling agent, the kind and the mixing condition of the coupling agent used for the surface treatment of the substrate such as glass cloth can be performed by a known method. As a treatment method, a general dipping method or spraying method can be used. A dipping method using ultrasonic waves (JP-A 63-165441) or a dipping method using a roller jet dehydrator (JP Sho 63-175165) can also be used.

  The proportion of the glass component in the prepreg of the present invention is preferably 10 to 70% by mass, more preferably 20 to 50% by mass based on the total amount of prepreg.

  Next, the substrate of the present invention will be described.

  The substrate of the present invention comprises at least a resin layer formed by curing the thermosetting resin composition of the present invention and / or a resin layer formed by curing the thermosetting resin composition in the prepreg of the present invention. is there. Alternatively, a conductor foil may be formed on the surface of these bases to form a substrate with a conductor foil.

  FIG. 1 is a perspective view schematically showing a substrate with a conductive foil according to a preferred embodiment. As shown in FIG. 1, the board | substrate 10 with a conductor foil of this embodiment is equipped with the resin layer 12 and the conductor foil layer 14 provided in both surfaces of this resin layer 12. As shown in FIG.

  The resin layer 12 includes a cured product of the above-described thermosetting resin composition of the present invention, and is preferably formed from the above-described prepreg of the present invention.

  The conductor foil layer 14 is not particularly limited as long as it is made of a conductor material usually used for circuit materials such as a circuit board, and is preferably selected from metals having good conductivity such as gold, silver, copper, and aluminum. You just have to choose one. Among these, a copper foil is preferably used from the viewpoints of cost and grade. The conductive foil layer 14 may be produced by either electrolytic method or rolling method. However, if the foil peel strength is desired, the electrolytic foil is used. A rolled foil with little effect can be used. The conductor foil layer 14 is preferably subjected to a surface treatment on at least the surface in contact with the resin layer 12. As the surface treatment for the conductor foil layer 14, in addition to the roughening treatment for forming irregularities, an alloy layer as exemplified in Japanese Patent No. 3295308 may be formed on the surface of the conductor foil layer 14. The thickness of the conductive foil layer 14 is preferably 8 to 70 μm, and more preferably 12 to 35 μm.

  The substrate 10 with conductor foil having such a configuration is obtained by, for example, stacking the conductor foil to be the conductor foil layer 14 on both sides of the prepreg described above, and heating and pressing the obtained laminate by a vacuum press or the like. It can be manufactured by processing the conductive foil so as to have a desired pattern. The layers of the prepreg and conductor foil are brought into close contact with each other by heating and pressurizing the laminate, and the resin composition in the prepreg is cured to form the resin layer 12. The heating and pressurization at this time are performed under the conditions of a temperature of 100 to 250 ° C. (more preferably 120 to 200 ° C.) and a pressure of 0.5 to 7.84 MPa (more preferably 0.5 to 4 MPa). It is preferable to carry out within a range of up to 20 hours, and the treatment may be repeated a plurality of times within these conditions. The patterning of the conductor foil can be appropriately performed by a known patterning method such as a photolithography method.

  In the production of the substrate 10 with conductor foil, before laminating the conductor foil as described above, for example, by forming the resin layer 12 first by heating the prepreg and curing the resin composition, Thereafter, the conductive foil layer 14 may be formed on the surface of the resin layer 12. Heating in the case of obtaining the resin layer 12 is preferably performed at 100 to 220 ° C, more preferably 120 to 200 ° C. Such heating may be performed by applying pressure while heating by, for example, a vacuum press.

  Since the resin layer 12 in the substrate 10 with conductor foil having such a structure mainly contains a cured product of the resin composition of the present invention, it has excellent flame retardancy, low dielectric constant and low dielectric loss tangent. Moreover, it is excellent in heat resistance and mechanical strength. For this reason, the circuit board obtained from the substrate 10 with the conductive foil can exhibit excellent flame retardancy even when mounted on an electronic device and exposed to high temperatures, is not easily deformed, and has a high frequency band. The signal can be transmitted with low loss.

  In addition, as a board | substrate with a conductor foil of this invention, you may have a structure other than the form mentioned above. For example, the board | substrate with conductor foil may be provided with the laminated substrate formed by laminating | stacking the resin layer mentioned above as a resin layer. FIG. 2 is a schematic cross-sectional view showing an example of a substrate with a conductive foil provided with a laminated substrate. As shown in the figure, the substrate 40 with conductive foil is composed of a laminated substrate 25 made of a resin layer 20 having an arbitrary number of layers (here, three layers), and a conductive foil 30 arranged on both surfaces of the laminated substrate 25. It is. The resin layer 20 is the same as the resin layer 12 of the above embodiment. Moreover, as the conductor foil 30, the thing similar to the conductor foil for forming the conductor foil layer 14 mentioned above is applicable. Such a substrate 40 with conductor foil can be used as a circuit board mounted on an electronic device or the like by processing the conductor foil 30 into a predetermined circuit pattern or the like.

  Further, if the above-described substrate with copper foil is used as a core substrate, a multilayer substrate can be easily formed. That is, by alternately laminating insulating layers and conductive foil layers on the outer layer of the substrate with copper foil, a multilayer substrate having alternating conductive foil layers and insulating layers can be easily obtained. In the multilayer substrate having such a structure, the resin layers 12 and 20 of the above embodiment may be used not only as a core substrate substrate but also as an insulating layer (interlayer substrate) disposed between conductor foil layers.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

(Examples 1-6 and Comparative Examples 1-12)
Vinyl benzyl ether (VBE) resin represented by the above general formula (1) (trade name: ARS-068, manufactured by Showa Polymer Co., Ltd.) and a phosphate ester represented by the following formula (5) (trade name: PX-200) Manufactured by Daihachi Chemical Co., Ltd.) and 2,2-bis (p = 2, R ⁷ = aryl group, R ⁸ = group represented by the above formula (III)) 3,4-dihydro-3-phenyl-1,3-benzoxazine) propane (trade name: Ba type benzoxazine, manufactured by Shikoku Kasei Kogyo Co., Ltd.) and an organic peroxide (dicumyl peroxide) as a crosslinking agent , Trade name: Park Mill D, manufactured by NOF Corporation) was dissolved in 50 parts by mass of toluene in the proportions (unit: parts by mass) shown in Tables 1 and 2 below to prepare a resin solution.

  To the obtained resin solution, an inorganic filler (barium-neodymium-titanium dielectric material, average particle size 1.6 μm, ε ′ = 90, tan δ = 0.00059, manufactured by TDK) is further added to the solid solution in the resin solution. It added so that the ratio of the inorganic filler which occupies for the total volume of a part might be 40 volume%, it mixed, and the solution of the thermosetting resin composition of Examples 1-6 and Comparative Examples 1-11 was produced. Moreover, the solution of the thermosetting resin composition of Comparative Example 12 was prepared in the same manner as in Example 5 except that the proportion of the inorganic filler in the total volume of the resin solution was 55% by volume.

  The thus obtained thermosetting resin composition solutions of Examples 1 to 6 and Comparative Examples 1 to 12 were formed on a film by a casting method, dried at 120 ° C. for 1 hour to remove the solvent, and the coating film. Formed. Thereafter, the coating film was pressed with a mold and cured in a vacuum at 200 ° C. for 5 hours to produce a substrate having a thickness of 1.2 mm.

[Characteristic evaluation test]
For the substrates obtained in Examples 1-6 and Comparative Examples 1-12, dielectric properties, flame retardancy, heat resistance, solvent resistance, mechanical strength, flexural modulus, and copper foil adhesion are as follows. Was evaluated. The results are summarized in Table 3.

(1) Dielectric constant ε ′ and dielectric loss tangent tan δ (dielectric property evaluation)
The substrate was cut into 90 mm × 1.5 mm × 0.8 mm and used as a sample for measuring dielectric properties. The measurement was performed at 2 GHz using a cavity resonator perturbation method.

(2) Flame-retardant evaluation The board | substrate was cut | disconnected to 127 mm x 12.7 mm x 0.8 mm, and this was made into the flame-retardant measurement sample. Using this measurement sample, a vertical combustion test was conducted in accordance with the UL94 standard, and V-0, V-1, V-2, and combustion (not applicable to V-0, V-1, and V-2) 4 Judged by one rank.

(3) Glass transition temperature (heat resistance evaluation)
The substrate was cut into 40 mm × 10 mm × 0.8 mm and used as a sample for measuring the glass transition temperature. The glass transition temperature (Tg) of the substrate was measured using a viscoelasticity measuring device (trade name: DMS6100, manufactured by Seiko Electronics Co., Ltd.) at a measurement frequency of 1 Hz.

(4) Evaluation of solvent resistance The substrate was cut into a width of 10 mm and a length of 30 mm, and this was used as a solvent resistance measurement sample. This measurement sample was immersed in toluene and treated with an ultrasonic cleaner for 10 minutes, and then mass measurement was performed. Thereby, the mass change rate of the measurement sample before and after the test was calculated, and the sample having the change rate of 0.1% or less was evaluated as ◯, and the sample having the change rate exceeding 0.1% was evaluated as ×.

(5) Evaluation of mechanical strength and bending elastic modulus The substrate was cut into a width of 20 mm and a length of 25 mm, and this was used as a measurement sample of mechanical strength and bending elastic modulus. The mechanical strength and flexural modulus of this measurement sample were measured according to the measurement method specified in JIS K7203.

(6) Copper foil adhesion evaluation The thermosetting resin composition solutions of Examples 1 to 6 and Comparative Examples 1 to 12 were respectively coated on an electrolytic copper foil (JTM 12 μm, manufactured by Nikko Materials) by the doctor blade method. After the processing, heating and drying were carried out at 120 ° C./10 minutes to obtain a copper foil with resin having a thickness of 70 μm. The FR-4 substrate from which the copper foil was peeled off was sandwiched between the obtained copper foils with resin, and applied with a vacuum press under conditions of a temperature profile of 120 ° C. for 30 minutes, 150 ° C. for 30 minutes, 180 ° C. for 6.5 hours, and a pressure of 2 MPa. The substrate was pressed and cured to produce a substrate (laminated substrate) having a thickness of 1.2 mm. This laminate with copper foil was cut into a width of 20 mm and a length of 100 mm, and this was used as a measurement sample for copper foil adhesion. After making two parallel cuts at a distance of 10 mm in the longitudinal direction on the surface of this measurement sample, a copper foil strip having a width of 10 mm is perpendicular to the surface using a tensile tester. It peeled in the direction at a speed of 50 mm / min. The minimum value of the stress measured here was defined as the copper foil adhesion.

  Moreover, although the glass cloth was impregnated with the thermosetting resin composition solution of Comparative Example 12 to prepare a prepreg, the coating film was easily removed from the surface. Using this, an attempt was made to produce a substrate with a vacuum press, but the coating film did not flow, and a substrate that could be handled as a substrate was not obtained.

  As is clear from the results shown in Table 3, according to the thermosetting resin composition of the present invention (Examples 1 to 6), the substrate was compared with the thermosetting resin compositions of Comparative Examples 1 to 12. It was confirmed that all of flame retardancy, dielectric properties in the high frequency region, heat resistance, solvent resistance, mechanical strength and copper foil adhesion can be achieved at a high level.

It is a perspective view which shows typically the board | substrate with a conductor foil which concerns on suitable embodiment. It is a schematic cross section which shows an example of a board | substrate with a conductor foil provided with a laminated substrate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Substrate with conductor foil, 12 ... Resin layer, 14 ... Conductor foil layer, 20 ... Resin layer, 25 ... Laminated substrate, 30 ... Conductor foil, 40 ... Substrate with conductor foil

Claims (12)

A vinyl benzyl ether compound represented by the following general formula (1), an aromatic phosphate ester, and a benzoxazine compound,
The content of the aromatic phosphate is 50 to 80 parts by mass with respect to 100 parts by mass of the vinyl benzyl ether compound, and the content of the benzoxazine compound is 5 to 40 parts by mass. Thermosetting resin composition.

[Wherein, R ¹ represents a methyl group or an ethyl group, R ² represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 2 to 6. ] The thermosetting resin composition according to claim 1, wherein the aromatic phosphate ester is represented by the following general formula (2).

[Wherein Q represents a divalent organic group having an aromatic ring or a divalent aliphatic hydrocarbon group having 2 to 14 carbon atoms, and R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom. Alternatively, it represents an alkyl group having 1 to 6 carbon atoms, k represents an integer of 1 or more, and m ¹ , m ² , m ³ and m ⁴ each independently represents an integer of 1 to 3. ]   The thermosetting resin composition according to claim 1 or 2, further comprising an inorganic filler having a dielectric loss tangent of 0.003 or less in a high frequency band of 2 GHz or more.   The thermosetting resin composition according to claim 3, wherein the content of the inorganic filler is 10 to 50% by volume based on the total solid volume in the thermosetting resin composition.   The thermosetting resin composition according to any one of claims 1 to 4, further comprising a radical polymerization initiator.   6. The thermosetting resin composition according to claim 5, wherein the content of the radical polymerization initiator is 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the vinyl benzyl ether compound.   A prepreg comprising a substrate impregnated with the thermosetting resin composition according to any one of claims 1 to 6.   The prepreg according to claim 7, wherein the substrate is at least one selected from the group consisting of a glass nonwoven fabric, a glass cloth, and an aramid nonwoven fabric.   The board | substrate provided with the resin layer formed by hardening | curing the thermosetting resin composition as described in any one of Claims 1-6.   The board | substrate provided with the resin layer formed by hardening | curing the said thermosetting resin composition in the prepreg of Claim 7 or 8.   A resin layer obtained by curing the thermosetting resin composition according to any one of claims 1 to 6, and a conductor foil disposed on the surface of the resin layer. A substrate with conductive foil.   A substrate with a conductor foil, comprising: a resin layer obtained by curing the thermosetting resin composition in the prepreg according to claim 7; and a conductor foil disposed on a surface of the resin layer. .

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